Automatic chain oiler for chain saw



April 21, 1959 A Ac. A. MATTsoN 2,883,000

AUTOMATIC CHAIN oILER Foa CHAIN sAw original Filed Feb. 17, 1953 v 4 sheets-sheet.;

IIT

April 2l, 1959 c. A. MA-r'rsoN 2,883,099

' AUTOMATIC CHAINV oILER FoR CHAIN sAw original Filed Feb. 17, 1953` l 4 Sheets-Sheet 2 N l w Mezz/#for v 65e/Me April 21, 1959 cffMAT-rsoN 'A AUTOMATIC CHAIN CILER Fox CHAIN sAw original Filed Feb. 17, 195s 4 Sheets-Sheet 3 April 2l, 1959 AUTOMATIC CHAIN OILER Foa CHAIN SAW original'Filed Feb. 17, 1953 y @06W y A Y Zag/595 jsvzz.

c. A. MA'rTsoN j 2,883,000

4 Sheets-Sheet 4 Unite rates AUTMATIC CHAN ILER FOR CHAIN SAW .Charles A. Mattson, Chicago, Ill., assignor, .by mesne assignments, to Remington Arms Company, Inc., Bridgeport, Conn., a corporation ot' Delaware .Continuation of application Serial No. 337,288, `February 17, 1953. This application October 15, 1956, Serial No. 616,072

13 Claims. .(Cl. 184'-15) This invention pertains to an automatic oiling device, and, more particularly, it pertains to an automatically op,- 4erated oiling device for use in a rotary power transmission unit such as a chain saw transmission.

This application is a continuation of my copending-application, Serial No. 337,288, led February 17, 1953 (now abandoned) which in turn was a continuation of `application Serial No. 272,995, led February 23, 1952 (also now abandoned).

An application of this invention is shown and described in connection with a gasoline engine chain saw unit wherein this invention is especially useful. In the operation of any chain saw ofthe-.well known types, the most ecient Operation depends upon proper lubrication of the chain and the contacting elements. Heretofore, the means of applying a lubricating oil tothe chain has been primarily a manually operated yoiling device. This device is not `satisfactory for` several reasons, such as the inconvenience tothe saw operator who is required to operate the oiler .Whilehe simultaneously holds and operates the saw, frequently using both hands on the saw. The lubricant is therefore not always applied at the time it is needed, thus causing periods vof saw operation withoutvproper lubrication. Also, the presently known lubricating mechanisms have parts which project from the transmission housing toibeaccessiblelto the saw. operator but subject to damaging forces and possible clogging by foreign matter. This also adds weight and bulk to. the chainsaw and, therefore, 4renders it less useful since alight weight saw is indispensable to the modern chain saw. Further, the lubricant is not applied directly-to thepoint where it is most needed inthe operation of the chain as the oil is placed on the top portion ofthe chain rather than the base portion which rides in the guide plate groove.

In addition to the foregoing, there also exists in the prior artmeans for automatically applying the necessary lubricating oil to the chain, An example of this prior art is shown in Fig. i7 of U.S. Patent 2,184,461 wherein an Vautomatic oiler is` described to operate oif a shaft eccen- `tricso that each shaft revolution releases oil through a :check valve to the chain. However, the prior art oilers are not practical :for reasons such as cumbersomeness, which increases both `weight yand volume of the chain saw; lack of adjustability in the amount of oil applied; Yand the lubricating device is located in the tailstock of the saw and notfin the transmission. New cutting `techniques have .eliminatedthe necessity of using a tail stock.

',Consistentwiththe foregoing comments, it isfan importantobject of-this `invention toprovide a chain saw `lubricating device whichis automatically operated with the. operation of the chainsaw.

Another important 4object is to provide Van lautomati- -cally yoperatedchain'saw lubricating device which supplies -a predetermined amount of lubricating oil to the chainat predeterminedv intervals.

jvStill .another object of this invention isto provide a chain saw lubricating' device which 'is disposed entirely Patented-Apr. 21, 1959 within the transmission housing thereby avoiding the pro- .jection of parts from the saw,

An additional important object is to provide an auto- Amatically operated chain saw lubricating device which is adjustable and can be readily adjusted without any disassembling of parts. Y

Still la further object of this invention is to provide an automatically operated chain saw lubricating device which is simple and inexpensive in construction and can be readily removed from its assembled position.

Another object is to provide a chain saw chain oiler .device which applies the lubricating oil directly to the sur- :face requiring it, i.e., the base portion of the chain. o

Other objects and advantages will become more readily apparent upon reading the following disclosure in light of -the accompanying drawings, in-which,

Fig. 1 is a fragmentary View of a portion of a chain saw wherein this invention is disposed.

Fig. 2 is a sectional view taken on the line 2-2 of Fig. l.

AFig. -3 is a horizontlal enlarged sectional view taken through a portionof Fig. 2 and showing a preferred embodiment of this invention.

Fig. 4 is a sectional view Vsimilar to that shown inFig. 3 4but showing a different position of the mechanism.

Fig. f5 is a sectional view taken on the line 5 5 of Fig. 3.

--Fig..6 is a sectional view similar to that of Fig. 3 but .showing a modification of this invention.

Fig. 7 is a sectional view similar to that of Fig. 3 but .-.showinga further-modiiication of this invention.

Similar reference numerals refer to similar parts `tlfiroughout the several views.

As shown in Fig. 1, the main parts viewed therein are the conventional mechanism of a gasoline engine driven chainsaw, but the view is included to assure a complete disclosure of this invention. Thus, there is generally shown a transmission housing 10 having a chain saw guide plate 11 mounted on the forward end while a gasoline entgine unit (not shown) would be mounted on the rear- -ward endiin a conventional manner. The guide plate 11 is bolted tothetforward end of the housing 10 and provides the track for guiding. the travel of a continuously `formed saw chain 13 which is wrapped therearound. A bracket member 14 is bolted with the guide plate 11 to the housing 10 whereby the bracket teeth 16 can bite into the workpiece, usually a Vtree or log, and control the ksaw during its operation.

It `will be further noted in Fig. 1 that a shaft 17 is rotatably mounted in the housing 10 to projecttherefrom and have a sprocket 18 preferably splined onto the projecting end of shaft 17 to be non-rotatable therewith. The chain 13 is engaged partially around the sprocket 18 to permit rotation Yof the latter topdrive the chain `on the guide plate 1.1. The periphery of the guide :plateis provided with a conventional groove wherein the .base of the chain travels, thereby providing the primary frictional contact for which the lubricant is relquired.

Thus, the foregoing describes a generally conventional means of `arranging the chain saw engine unit, the 'transmission unit, `and the chain andguide plate to eifect rotation of the shaft 17 and sprocket 18 and thereby .drive the chain in acontinuous and desired operation.

The View shown in Fig. 2 comprises the transmission `housing 10 shown to include an oil reservoir portion 21 lwhich is fluid tight by means of two plugs 22 being threadedtherein. Again the forward end ofthe housing 10 shows the means for mounting the guide plate 11 and the bracket 14 thereon through bolts 23.engaging the housing. The rearward portion of the housing 10 con- 3 tains an integral flange 24 through which the housing is clamped to the engine unit in the usual manner. Also, as seen in the rearward housing portion, adjacent the engine unit, a clutch drum 26 is mounted on a shaft 27 which in turn is rotatably mounted in the housing 10, by means of two bearings 28 and 30, in the usual manner. The bearing 28 is secured to the transmission with a retainer member 29 abutting the bearing and a plu rality of screws 31 fastening the retainer 29 to the housing 10. The outer end of shaft 27 is preferably threaded to connect to the clutch drum 26 which thereby transmits rotation to the shaft 27. An intermediate portion of the shaft 27 has a bevel gear 32 keyed thereon to mesh with a bevel gear 33 which is keyed to the main transmission shaft 17 to rotate the latter.

The shaft 17 is supported in the housing 10 by means of an inner housing wall portion 36 which is provided with an opening to receive a shaft bearing member 37. The outer end portion of shaft 17 is supported by a bearing member 38 which is positioned within a cover 39 secured to the housing 10 by a plurality of screws 41 engaging the housing. A retainer member 42 is fastened to the cover 39 by screws 43 and thereby retains the bearing 38 in position.

It will be understood that the outer end portion of shaft 17 is preferably splined to receive the sprocket 18 in a driving relation as the latter member is secured to the shaft by a washer 46 and a nut 47 which is threaded onto the shaft 17. The usual spacer 51 and washer 52 are provided on the shaft 17 inside the sprocket 18 to space the latter from the retainer 42. The end portions of shaft 17 are provided with fluid seal members 48 and 49 to prevent fluid, either oil or air, from passing along the exterior of the shaft.

The foregoing describes a conventional construction of a transmission as commonly employed in a chain saw, while the following deals with the essence of this invention.

Referring to the shaft 17 as shown in Fig. 3, it will be noted that the shaft is provided with an axial bore 56 at its inner end portion and a transverse opening 57 extending through the side of the shaft 17 to communicate with bore 56. It should be noted that opening 57 is located between two preferably annular fluid seal members 49. Snugly disposed Within bore S6 is a pump element, such as a piston lor plunger member 58, which is free to move axially within the bore while it effectively seals between the bore 56 and the piston external surface to prevent air or oil from passing therearound. The piston 58 is further provided with lan axial opening 61, extending along a central portion, and a transverse opening 62 in communication with opening 61. Thus, it will be apparent from Fig. 3 that the transverse openings 57V and 62 of the shaft 17 and the piston 58, respectively, are located to align when the shaft 17 is in a particular position of operation, such as that shown in Fig. 3, and thereby provide a ow passage from outside the shaft 17 to the inside thereof and to the axis of the piston 58.

Opposite ends ofthe piston 58 are shown to be provided with enlarged axial bores 63 which communicate with the piston opening 61. Through one of the piston bores 63, the shaft 17 is provided with a pin 64 to extend therethrough and across the piston 58 at an end portion provided with a slot 66 in the piston S8. Thus, as better shown in Fig. 5, the shaft 17 and the piston 58 are in rotary driving relation by the arrangement of pin 64 passing through the slot 66, while ian axial movement of the piston 58 relative to the shaft 17 is possible.

The other end section of the shaft 17 contains an axial opening 67 which extends from the bore 56 to the endl of the sha-ft 17 where a shaft bore 68 is provided to align with the opening 67. Bore 68 contains an internally threaded portion to receive a plug 71 which renders 'the shaft end fluid tight.

Thus, it will be noted that a continuous flow passage .4 is provided from the shaft and piston transverse open ings 57 and 62, respectively, to the piston openings 61 and 63, to the shaft bore 56 and to the shaft opening 67 and the shaft bore 68. The means for electing the flow of lubricating oil along the above referred to passage is preferably as described hereinafter.

As shown in Fig. 3, two oppositely disposed ball check valves 73 and 74 are located at opposite end portions of the shaft 17 with valve 73 being located at the outer end of the piston opening 61 and valve 74 being located at the outer end of shaft opening 67. The valves 73 and 74 are provided with coil springs 76 and 77, respectively, which yieldingly urge the valves to their seats as shown in the position in Fig. 3. A spring stop 78 is threaded into the outer end portion of the piston 58 to support the spring 76 in its position. The stop 78 con tains an axial opening 79 to permit fluid passing through the valve 73 to pass from the piston end. Also, the plug 71 in the opposite end of shaft 17 serves as a support for the spring 77 which acts against the valve 74. In connection with this arrangement, it should be noted that the plug 71 is readily available from the exterior of the transmission housing as shown in Fig. l, and it can be easily adjusted by means of a screwdriver slot 75, to provide the desired action of the valve 74 by regulating the compression on spring 77. By relative adjustment of the spring forces which must be overcome before oil will pass through the respective check valves 73 and 74, it is possible to control the proportion owing through each valve with reference to the total amount to be discharged with each pumping stroke. Thus, in this invention, an adjustment is simply provided for controlling the relative proportion of oil which will pass through valve 74 as the plunger descends.

Referring again to Fig. 3, it will be apparent that during the operation of the saw, the shaft 17 is rotated through gear 33 thereby rotating the piston 58 through the pin 64. As the piston rotates, a piston projecting end portion 81 acts as a follower on an adjacent cam member 82 which is circular in cross sectional shape and pressed into the transmission housing 10. Thus, the cam 82 has a at face surface which is inclined to the axis of rotation of the piston 58 and causes the piston to be axially displaced toward the center of the shaft 17 to the position shown in Fig. 4 upon 180 degree rotation from the'position shown in Fig. 3.

In moving from the position shown in Fig. 3 to the position shown in Fig. 4, fluid present between the check valves 73 and 74 will be forced therefrom in an amount substantially equal to the amount of fluid drawn into the bore at the end of the pistons reciprocation cyclethat is, during the instant when the transverse passage 62 of the piston icommunicates with transverse opening 57. Since the diameter of opening 57 is substantially less than the diameter of bore 56 (Figs. 3 and 4), and since uid is drawn into the bore only at the moment when the transverse openings of the shaft and reciprocable piston are in direct communication, it is apparent that the volume of fluid pumped during a single pumping stroke of the piston will be substantially less than the displacement of that piston. Depending upon either the relative strength of springs 76 and 77, or upon the preloading of these springs by their respective support members, the relative pressure responsiveness of the valves and hence the proportionate quantity of uid passing .through each valve is regulated in relation to the total vuid pumped. Fluid passing through the valve 74 enters the shaft bore 68 where it passes to a transverse shaft opening 87 Which is in constant communication with a 4passage 86 extending radially in the sprocket 18.

It should thus be understood that the piston executes its pumping stroke during a degree angle of rotation of the shaft 17, and that lubricant is discharged from the .sprocket 18 and onto the chain 13 along an arc of rotation substantially less than 180 degrees. The exact i V "timing of the lubricant discharge Acan be varied as desired but is preferably as s'hown V-in"`Fig. l to coverthe .smaller .segment of rotation between .the lines `designated j j Upon the continued rotation of the shaft V17 from the position shown in Fig. 4 to the position shown in Fig. v3, a coil spring 91, which is positioned withinthe shaft bore 56 Vand abuts the piston '58, urges the latter `outwardly against the cam 82. This piston return action creates a slight vacuum in the'passage between cheek valves 73 and 74. Then, as the piston opening 62 ap- -proa'ches alignment with vthe opening y5.7, oil is educted from athereservoir .21 through a exible tube 92,.shown .in Fig. 2, `and the nipple 93 which is ,in communication with .the .chamber -94 between the two annular seals 49. The oil .then passes into .the .passage ybetween the check walves 73 and 74 to relieve the vacuum createdtherein .and to restore the original condition prior to another pumping -stroke of the piston 58.

To assure continuous contact of the tube 92 with the oil in the reservoir 21, it .is preferred that a freeweight 96 .be placed on'the -end of the tube 92'to maintain the tube end submerged lin oil regardless of `the position of the transmission housing or the .level of the .oil in the reservoir 21.

Obviously, from the foregoing description it .should be realized Vthat variations exist within the scope of that disclosure. One such variation is the elimination of check valve 73 andthe uid passage upon which it operates, fsuch as passage 79. Then the oil in shaft bore 56 would be pumped y,therefrom through the valve 74 fwithout the return ilow through valve 73.

Furtlrer modifications-'of the foregoing invention yare shown in Figs. 6 and 7. Here the parts, corresponding `to those ofthe foregoing, are referenced with the same 'numbers.

The modiicationshownin Fig. 6 consists generally of the elimination of the spring 91 of Figs. 3 and'4, and

the provision of a cam and a follower which replace the `*function of the spring by positiveactua-tion of the piston upon rotation of the shaft 17. In Fig. 6, transmission housing 10 is slightly modified'from that shown in Fig. 3

in order to accommodate the modified cam 100 and follower 101. Cam 100 is preferably pressed into opening 99 of housing v10 and is provided with a helical groove 102 which receives end portion 103 of follower "101.

`It should be noted that pump piston `104 is a'lso slightly .modified from piston S8 so that the projecting end thereof is clamped to follower 101 by set screw 106 or similar means. The piston 104 and follower 101 are thus relatively .non-.rotatably secured together. Piston 104 is fluid tightly disposed within shaft bore 56 to be axially movable therewithin but relatively non-rotatable with shaft 17 by virtue of -pin 64 in slot 66.

The operation of the construction of Fig. 6 is such that upon rotation of shaft 17 by gear 33 and through key 108, the cam 100 and follower 101 act to move piston 104 axially as pin 64 rotates piston 104. This eifects the uid pumping operation as previously described. Upon rotation of 180 degrees from the position shown in Fig. 6, to that shown in Fig. 4, the oil inlet 57 is closed and fluid is pumped through piston bore 61 in either direction depending upon the outlet adjustment.

Fig. 7 shows a further modification of the invention shown in Figs. 3 and 4. Here the piston is maintained non-rotatable but axially movable. The housing 10 is altered from that previously described to provide a circular bore 110 aligned with shaft 17. Pump piston 111 is snugly fitted within shaft bore 56 to be axially movable therewithin. Piston 111 extends from shaft 17 to project within bore 110. The end of piston 111 contains a slot 112, similar to slot 66 shown in Pig. 5. Slot 112 receives transversely extending pin 113 which is rigidly mounted in housing 10. Pin 113 then maintains piston '111 in a `non-rotatable position while permitting axial movement of the same.

Positioned between the base of bore and the end of piston 111 is a 4compression spring 114 which urges piston 11'1 into shaft bore 56. The opposite end of piston 111 contains a cam follower 116. Adjacent this end is a cam 117 preferably pressed into `shaft bore 56 and provided with a iiuid passage 118. Thus, it should be understood that spring 114 and cam 117 govern the .axial movement of piston 111.

Upon rotation of shaft 17, piston 111 is maintained non-rotatable by pin 113. However, cam 117 rotates with shaft 17, and, therefore, permits spring 114 to axially move piston 111 downwardly from the position shown in Fig. 7. This effects the closing of inlet 57 and the fluid pumping stroke, passing uid through bores 61, 118 and 67. Depending upon the adjustment of the valves 73 and 74, uid will also pass through bores 61, 63, and 79, and then through transverse opening 119 in piston 111 to permit the oil to return to the reservoir 21.

Although this invention has been described in a specific embodiment, it should be understood that numerous changes canbe made within its scope, and this invention should, therefore, be limited only by the appended claims.

I claim:

l. In a chain saw having -a driven shaft equipped with a chain driving sprocket mounted thereon, said sprocket being provided with a passage extending inwardly from the periphery thereof, said shaft providing an axially extending bore therein and providing a passage in communication with said bore and said sprocket passage, check valve means provided by said shaft for permitting the flow of oil from said bore to said sprocket and for preventing oil flow in the opposite direction, oil reservoir means provided by said chain saw, passage providing means extending from said reservoir to said shaft, said shaft having a port in the wall thereof communicating with said bore and with said passage providing means, a plunger reciprocably mounted within said bore for driving oil to said sprocket passage from said bore, said plunger being arranged 'to close said port during all of its reciprocation cycle except when said plunger is substantially at the end of said cycle, said port being sufiiciently smaller in diameter than said bore so that at substantially the end of each plunger cycle said bore receives an increment of oil from said reservoir substantially less than the amount which would cause said plunger todischarge oil to said sprocket throughout its full stroke away from said port, and means for reciprocating said plungerin timed sequence with vthe rotation of said shaft and sprocket, whereby the period of oil ldischarge through said relation with said chain.

2. The structure of claim l in which means are provided for preventing rotation of said plunger with reference to said chain saw and for permitting reciprocation of said plunger within the bore of said rotatable shaft.

3. The structure of claim l in which means are provided for constraining said plunger for rotation with said shaft while permitting said plunger to reciprocate within said bore.

4. The structure of claim 3 in which the means for reciprocating said plunger upon rotation of said shaft comprises a cam member having a cam surface angled with reference to the axis of shaft rotation, said plunger being provided with a cam rider portion adapted to engage said angled :cam surface, and means biasing said plunger so that said rider portion is in constant engagement with said angled cam surface.

5. The structure of claim 3 in which the means for reciprocating said plunger upon rotation o-f said shaft comprises a cam member having a continuous cam groove extending along a plane angled with reference to the axis of shaft rotation, said plunger being provided with a carn rider portion adapted to ride within said groove for reciprocating said plungerupon rotation of said shaft with reference to said cam member.

6. In a chain saw having a driven shaft equipped with Y.

a chain driving sprocket mounted thereon, said sprocket being constructed and arranged to contact a saw chain along an arc of its periphery of substantially less than 180 and having a passage extending centrally towards the sprockets rotational axis from the periphery thereof,

said shaft providing an axial bore therein and having' said bore for axial movement between an inner and an outer position, said plunger being arranged to cover said shaft port during all of its reciprocation cycle except when said plunger is near its outer position, said port being in open communication with said bore when said port is uncovered by said plunger, said port being sufcientlyl smaller in diameter than said bore so that as said plunger nears its outer position said bore receives an increment of lubricant from said reservoir substantially less than the amount which would cause said plunger to discharge lubricant to said sprocket through its full stroke towards said inner position, and means for reciprocating said plunger in timed sequence with the rotation of said shaft and sprocket, whereby the period of lubricant discharge through said sprocket passage can be confined to the portion of each sprocket revolution during which said sprocket passage is in direct lubricant discharging relation with said chain.

7. The structure of claim 6 in which said reciprocable plunger is provided with a ow passage therethrough in constant communication with said bore and in communication with said port Aonly when Isaid plunger is near its outer position.

8. The structure of claim 6 in which said passage providing means includes a pair of annular uid seal bearing members extending about said shaft on opposite sides of said port, said fluid seal members being spaced apart and defining an annular chamber about said shaft in constant communication with said port.

9. The structure of claim 6 in which means are pro- 50 vided for preventing rotation of said plunger with reference to said chain saw and for permitting reciprocation of said plunger within the bore of said rotatable shaft.

10. The structure of claim 6 in which means are pro- .vided for constraining said plunger for rotation with said shaft while permitting Asaid plunger to reciprocate within said'bore. "I l `1l. In a chain saw having a driven shaft equipped with a chain driving sprocket mounted thereon, said sprocket 'being provided with a passage extending centrally from the periphery thereof, said shaft providing an axially exltending bore therein and having a passage communicating :with said sprocket passage and said bore, oil reservoir means provided by said chain saw, passage providing means extending from said reservoir to said shaft, said shaft having an opening in the Wall thereof for placing `said passage ,providing means and said bore in communie cation, la plunger reoiprocablymounted within said bore 15 said plunger'being provided with an internal flow passage for driving oil `from said bore to said sprocket passage,

having a peripheral inlet alignable with said s'haft opening and having outlets at the ends thereof communicating with said bore at opposite ends of said plunger, said plunger being adaptedI to close said opening of said shaft during all of its reciprocation cycle except when the passage inlet of the same is in direct communication with said opening, a rst check valve provided by said shaft between said sprocket passage and said plunger for permitting -the flow of oil from said bore to said sprocket passage and for preventing oil ow in the opposite direction, a second oheck valve provided by said plunger for controlling the flow of oil through the axial passage of said plunger in a direction away from said sprocket, means cooperating with said check valves to adjust the same for regulating the relative proportion of oil passing through the respective check valves upon reciprocation of said plunger, and means for reciprocating said plunger in timed sequence with the rotation of said shaft and sprocket.

12. The structure of claim 11 in which means are pro- Avided for constraining said plunger for rotation with said References Cited in the file of this patent UNITED STATES PATENTS 766,756 Chapman Aug. 2, 1904 807,731 Dodge Dec. 19, 1905 1,445,285 Borgo Feb. 13, 1923 FOREIGN PATENTS Great Britain Apr. 9, 1925 

